One possibility to protect earthdams against strong hydrodynamic loading by overtopping water is to apply a slope protection layer with stones.
For a riprap slope protection and a stonemattress wrapped by a geogrid the two failure mechanisms "erosion of a single stone" and "sliding of the whole
slope protection layer" have been determined by dint of modell tests. The single stone erosion criteria is based on statistics while for the sliding of the
whole slope protection layer a deterministic approach has been chosen. For the use of cohesive soils stabilised with lime or cement as suitable construction
materials for dams that are subject to overtopping, an important criterion is their permanent resistance against erosion under all weather conditions. Tests on
stabilised samples have shown a great improvement of the resistance against erosion. Uniaxial compression tests were performed to examine the influence of
different types of binders, their added shares and the time for setting. On mixtures of soil and binder that have shown great resistance to frost, thawing ,
drying and wetting erosion tests were performed right after they have been subject to frost and thawing in a climatic chamber. They have still shown a great
resistance against erosion. Furthermore a new non-invasive seepage detection method for earthdams has been tested. It has been found that this method is a
convenient alternative to other geophysical methods.